TW201840915A - Plating apparatus and method for determining plating bath configuration - Google Patents

Abstract

There is provided a plating apparatus for plating a rectangular substrate using a substrate holder holding the rectangular substrate. The plating apparatus comprises a plating bath configured to store the substrate holder holding the rectangular substrate, and an anode disposed inside the plating bath so as to face the substrate holder. The substrate holder includes an electrical contact configured to feed two opposite sides of the rectangular substrate. The rectangular substrate and the anode are placed inside the plating bath so as to satisfy the relationship of 0.59 * L1-43.5 mm ≤ D ≤ 10.58 * L1-19.8 mm, where L1 is the shortest distance between a substrate center of the rectangular substrate and the electrical contact, and D1 is the distance between the rectangular substrate and the anode.

Description

 Method for determining plating structure and plating groove structure  

The present invention relates to a plating apparatus and a method of determining the structure of a plating tank.

Conventionally, wirings, bumps (protruding electrodes), and the like are formed on the surface of a substrate such as a semiconductor wafer or a printed substrate. As a method of forming the wiring, the bump, and the like, an electrolytic plating method is conventionally known.

In the plating apparatus used in the electrolytic plating method, for example, a circular substrate such as a wafer having a diameter of 300 mm is subjected to a plating treatment. However, in recent years, it is not limited to such a circular substrate, and in view of cost-effectiveness, in the semiconductor market, the demand for a square substrate has increased, and it is necessary to clean, polish, or plate a square substrate.

The plating apparatus has a plating tank in which, for example, a substrate holder holding a substrate, an anode holder holding an anode, an adjustment plate (a shielding plate), and the like are housed. It is known that in such a plating apparatus, the distance (electrode distance) between the electrodes from the substrate to the anode affects the uniformity of the film thickness formed on the substrate. Therefore, conventionally, in the plating apparatus, the distance between the poles is adjusted (for example, refer to Patent Document 1, Patent Document 2, and the like). Further, in the plating apparatus, in addition to the inter-electrode distance, the opening shape and the installation position of the adjustment plate, and the opening shape of the anode mask which the anode holder has, etc., also produce uniformity of the film thickness formed on the substrate. influences.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. 63-270488

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2002-226993

The optimum interelectrode distance of the plating apparatus varies depending on the size of the substrate. Conventionally, an appropriate inter-electrode distance for the size of each substrate is determined according to the rule of thumb, and the optimum inter-electrode distance is approximated by fine adjustment. However, since it is time consuming to finely adjust the inter-electrode distance by the operator's measurement, it is not always possible to find an optimum inter-electrode distance.

Further, since the circular substrate such as a wafer mainly has dimensions such as 150 mm, 200 mm, and 300 mm, it is relatively easy to determine an appropriate inter-electrode distance according to an empirical rule. However, from the current situation, square substrates have no specific size specifications and use various sizes. Therefore, it is difficult to determine the inter-electrode distances applicable to square substrates of various sizes by a rule of thumb as compared with a circular substrate. Further, since the inter-electrode distance affects the film thickness of the entire substrate, if the distance between the electrodes is deviated, an in-plane of a sufficient film thickness cannot be achieved in the adjustment of the opening size of the anode mask and the adjustment plate for adjusting the electric field. Uniformity.

The inventors of the present invention have earnestly studied and found that in the case of supplying power to the opposite sides of the square substrate, there is a predetermined correlation between the distance from the center of the square substrate to the contact and the appropriate inter-electrode distance. It is an object of the present invention to easily obtain an appropriate inter-electrode distance corresponding to a square substrate.

According to an aspect of the present invention, a plating apparatus for plating the square substrate using a substrate holder holding a square substrate is provided. The plating apparatus includes a plating tank configured to house the substrate holder holding the square substrate, and an anode, the anode being disposed opposite to the substrate holder on the plating The inside of the slot. The substrate holder has electrical contacts, and the electrical contacts are configured to supply power to opposite sides of the square substrate. In the case where the shortest distance between the center of the substrate of the square substrate and the electrical contact is L1, and the distance between the square substrate and the anode is D1, the square substrate and the anode satisfy 0.59×L1-43.5mm D1 A relationship of 0.58 × L 1-19.8 mm is disposed in the plating tank.

According to another aspect of the present invention, there is provided a method of determining a plating tank housing: a substrate holder holding a square substrate; and an anode holding of an anode mask holding the anode and shielding a part of the anode And an adjustment plate disposed between the substrate holder and the anode holder, wherein the method of determining the plating groove structure determines an opening shape of the anode mask and a cylindrical portion of the adjustment plate The opening shape, the distance between the square substrate and the anode, the distance between the square substrate and the cylindrical portion of the adjustment plate, and the length of the tubular portion of the adjustment plate. In the first step, the opening of the anode mask that minimizes fluctuations in the film thickness distribution of the square substrate is determined in a state where the respective values other than the opening shape of the anode mask are set to predetermined values. In the second step, the respective values other than the opening shape of the anode mask and the opening shape of the tubular portion of the adjustment plate are set to predetermined values, and the opening of the anode mask is opened. In the state in which the shape is the value determined in the first step, the numerical value of the opening shape of the tubular portion of the adjustment plate that minimizes the fluctuation in the film thickness distribution of the square substrate is determined; Each value of the distance between the square substrate and the adjustment plate and the length of the tubular portion of the adjustment plate is a predetermined value, and the opening shape of the anode mask is a value determined in the first step. The square substrate and the chamber having the smallest fluctuation in the film thickness distribution of the square substrate in a state in which the opening shape of the tubular portion of the adjustment plate is a value determined in the second step The numerical value of the distance of the anode; in the fourth step, the numerical value of the length of the tubular portion of the adjustment plate is set to a predetermined value, and the opening shape of the anode mask is determined in the first step. The value is such that the opening shape of the tubular portion of the adjustment plate is a value determined in the second step, and the distance between the square substrate and the anode is a value determined in the third step. a state in which the distance between the square substrate and the adjustment plate having the smallest fluctuation in the film thickness distribution of the square substrate is determined; and in the fifth step, the opening shape of the anode mask is made to be in the first process The value determined in the middle is such that the opening shape of the tubular portion of the adjustment plate is a value determined in the second step, and the distance between the square substrate and the anode is changed in the third step. The value of the adjustment plate is determined such that the distance between the square substrate and the adjustment plate is a value determined in the fourth step, and the adjustment plate having the smallest fluctuation in the film thickness distribution of the square substrate is determined. The length of the cylindrical portion.

11‧‧‧Substrate holder

39‧‧‧ plating tank

50‧‧‧Adjustment board

51‧‧‧Cylinder

60‧‧‧Anode cage

62‧‧‧Anode

64‧‧‧Anode mask

S1‧‧‧ square substrate

Fig. 1 is an overall layout view of a plating apparatus of the present embodiment.

Fig. 2 is a schematic plan view of a substrate holder used in the plating apparatus shown in Fig. 1;

Fig. 3 is a schematic plan view of a square substrate held by the substrate holder shown in Fig. 2;

Fig. 4 is a schematic longitudinal cross-sectional front view showing a plating tank and an overflow tank of the treatment unit shown in Fig. 1;

Fig. 5 is a partial plan view of the plating tank shown in Fig. 4;

Fig. 6 is a flow chart showing an analysis procedure for determining the inter-electrode distance D1, the distance A1, the length B1, and the distance B'1.

Fig. 7 is a graph showing the correlation between the inter-electrode distance D1 obtained by the analysis process shown in Fig. 6 and the distance L1 from the center of the square substrate to the electrical contact.

FIG. 8 is a graph showing the correlation between the distance A1 obtained by the analysis process shown in FIG. 6 and the distance L1 from the center of the square substrate to the electrical contact.

Fig. 9 is a graph showing the correlation between the length B1 obtained by the analysis process shown in Fig. 6 and the distance L1 from the center of the square substrate to the electrical contact.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding components are denoted by the same reference numerals, and the repeated description is omitted. Fig. 1 is an overall layout view of a plating apparatus of the present embodiment. As shown in FIG. 1, the plating apparatus 100 is roughly divided into an attachment/detachment part 110 in which a square substrate is mounted on a substrate holder or a square substrate from a substrate holder, a processing unit 120 that processes a square substrate, and a cleaning unit. 20. The processing unit 120 further includes a pre-processing ‧ a post-processing unit 120A that performs pre-processing and post-processing of the square substrate, and a plating processing unit 120B that performs a plating process on the square substrate. The attachment/detachment portion 110, the treatment portion 120, and the cleaning portion 20 of the plating apparatus 100 are surrounded by different frames (frames).

The attachment/detachment portion 110 has two cassette stages 25 and a substrate loading and unloading mechanism 29. The cassette 25 is mounted with a case 25a that houses a square substrate. The substrate attaching and detaching mechanism 29 is configured to attach and detach the square substrate to a substrate holder (not shown). Further, a housing portion 30 for housing the substrate holder is provided in the vicinity (for example, below) of the substrate attaching and detaching mechanism 29. In the center of these units 25, 29, and 30, a substrate transfer device 27 composed of a transfer robot that transports a square substrate between these units is disposed. The substrate transfer device 27 is configured to be travelable by the travel mechanism 28 .

The cleaning unit 20 has a cleaning device 20a that cleans and polishes the square substrate after the plating treatment. The substrate transfer device 27 transports the square substrate after the plating treatment to the cleaning device 20a, and takes out the cleaned and dried square substrate from the cleaning device 20a.

The pre-treatment ‧ post-processing unit 120A has a pre-wet tank 32, a pre-dip tank 33, a pre-wash tank 34, a blowing tank 35, and a washing tank 36. In the pre-wet groove 32, the square substrate is immersed in pure water. In the prepreg 33, an oxide film on the surface of a conductive layer such as a seed layer formed on the surface of the square substrate is removed by etching. In the pre-washing tank 34, the pre-impregnated square substrate is washed together with the substrate holder by a cleaning liquid (pure water or the like). In the blowing groove 35, the cleaning of the square substrate after washing is performed. In the washing tub 36, the plated square substrate is washed with a cleaning liquid together with the substrate holder. The pre-wet tank 32, the prepreg 33, the pre-wash tank 34, the blowing tank 35, and the washing tank 36 are arranged in this order.

The plating treatment portion 120B has a plurality of plating grooves 39 including an overflow groove 38. Each of the plating tanks 39 accommodates a square substrate therein, and the square substrate is immersed in the plating liquid held inside, and plated on the surface of the square substrate by copper plating or the like. Here, the type of the plating solution is not particularly limited, and various plating solutions are used depending on the application.

The plating apparatus 100 has a substrate holder transporting device 37 which is disposed on the side of each of the devices and transports the substrate holder together with the square substrate, for example, by a linear motor type. The substrate holder transporting device 37 is configured to transport the substrate holder between the substrate attaching and detaching mechanism 29, the pre-wet groove 32, the prepreg 33, the pre-washing tank 34, the blowing groove 35, the washing tub 36, and the plating tank 39.

Fig. 2 is a schematic plan view of a substrate holder used in the plating apparatus shown in Fig. 1; Fig. 3 is a schematic plan view of a square substrate held by the substrate holder shown in Fig. 2; As shown in FIG. 2, the substrate holder 11 has, for example, a flat substrate holder main body 12 made of polyvinyl chloride, and an arm portion 13 coupled to the substrate holder main body 12. The arm portion 13 has a pair of pedestals 14, and the susceptor 14 is provided on the upper surface of the peripheral wall of each of the processing tanks shown in Fig. 1, so that the substrate holder 11 is vertically suspended. Further, the arm portion 13 is provided with a connecting portion 15 which is configured to come into contact with an electrical contact provided in the plating groove 39 when the pedestal 14 is provided on the upper surface of the peripheral wall of the plating groove 39. Thereby, the substrate holder 11 is electrically connected to the external power source, and a voltage and a current are applied to the square substrate held by the substrate holder 11.

The substrate holder 11 is held exposed to the plated surface of the square substrate S1 shown in FIG. The substrate holder 11 has an electrical contact (not shown) that is in contact with the surface of the square substrate S1. When the substrate holder 11 holds the square substrate S1, the electrical contacts are configured to be in contact with the contact position CP1 shown in FIG. 3 provided along the opposite sides of the square substrate S1. Further, the square substrate has a square or rectangular shape. In the case of a rectangular square substrate, the electrical contacts are configured to be in contact with any of the opposite sides of the long side or the short side of the rectangular square substrate.

FIG. 4 is a schematic longitudinal cross-sectional front view showing the plating tank 39 and the overflow tank 38 of the processing unit 120B shown in FIG. 1 . As shown in FIG. 4, the plating tank 39 holds the plating liquid Q inside. The overflow groove 38 is provided on the outer circumference of the plating tank 39 to receive the plating liquid Q overflowing from the edge of the plating tank 39. One end of the plating liquid supply path 40 having the pump P is connected to the bottom of the overflow tank 38. The other end of the plating liquid supply path 40 is connected to the plating liquid supply port 43 provided at the bottom of the plating tank 39. Thereby, the plating liquid Q remaining in the overflow tank 38 is returned to the plating tank 39 as the pump P is driven. In the plating solution supply path 40, a thermostat unit 41 that adjusts the temperature of the plating solution Q and a screening program 42 that removes foreign matter in the plating solution are provided on the downstream side of the pump P.

The substrate holder 11 holding the square substrate S1 is accommodated in the plating tank 39. The substrate holder 11 is disposed in the plating tank 39 such that the square substrate S1 is immersed in the plating solution Q in a vertical state. An anode 62 held by the anode holder 60 is disposed at a position facing the square substrate S1 in the plating tank 39. As the anode 62, for example, phosphorus-containing copper can be used. An anode mask 64 that blocks a portion of the anode 62 is provided on the front side of the anode holder 60 (the side opposite to the square substrate S1). The anode mask 64 has an opening through which a power line between the anode 62 and the square substrate S1 passes. The square substrate S1 and the anode 62 are electrically connected via a plating power source 44, and a plating film (copper film) is formed on the surface of the square substrate S1 by flowing a current between the square substrate S1 and the anode 62.

A stir bar 45 that reciprocates parallel to the surface of the square substrate S1 and agitates the plating solution Q is disposed between the square substrate S1 and the anode 62. By stirring the plating solution Q by the stirring bar 45, sufficient copper ions can be uniformly supplied to the surface of the square substrate S1. Further, an adjustment plate 50 made of a dielectric for distributing the potential distribution over the entire surface of the square substrate S1 is disposed between the stir bar 45 and the anode 62. The adjustment plate 50 has a flat main body portion 52 and a cylindrical portion 51 that forms an opening through which a power line passes.

Fig. 5 is a partial plan view of the plating tank 39 shown in Fig. 4 . In Fig. 5, the stir bar 45 is omitted. As shown in FIG. 5, the square substrate S1 and the anode 62 are disposed to face each other with a distance D1. That is, the plating tank 39 has the inter-electrode distance D1. The cylindrical portion 51 of the adjustment plate 50 has a length B1. One end surface of the cylindrical portion 51 of the adjustment plate 50 is separated from the square substrate S1 by a distance A1. Further, the other end surface of the cylindrical portion 51 of the regulating plate 50 is separated from the anode mask 64 by a distance B'1. The electrical contact 16 of the substrate holder 11 is in contact with a portion at a distance L1 from the center of the square substrate S1.

As described above, in the plating tank 39, when the square substrate S1 is plated, the inter-electrode distance D1 affects the uniformity of the film thickness formed on the square substrate S1. Similarly, the appropriate distance A1 between the tubular portion 51 and the square substrate S1, the length B1 of the tubular portion 51, and the distance B'1 between the cylindrical portion 51 and the anode mask 64 are also applied to the film formed on the square substrate S1. Thick uniformity has an effect. Therefore, in order to obtain good in-plane uniformity of the film thickness, it is necessary to determine at least one of the appropriate inter-electrode distance D1, the distance A1, the length B1, and the distance B'1. The inventors of the present invention have earnestly studied and found that, in the case of supplying power to the opposite sides of the square substrate S1 shown in Fig. 5, the distance L1 from the center of the square substrate S1 to the electrical contact 16 and the appropriate pole There is a prescribed correlation between the distances D1. Also, the inventors of the present invention found that the distance L1 from the center of the square substrate S1 to the electrical contact 16 and the appropriate distance A1 between the cylindrical portion 51 and the square substrate S1, and from the center of the square substrate S1 to electrical connection The distance L1 between the points 16 and the length B1 of the tubular portion 51 have a predetermined correlation.

Fig. 6 is a flow chart showing an analysis procedure for determining the inter-electrode distance D1, the distance A1, the length B1, and the distance B'1. The analysis process shown in FIG. 6 is roughly divided into a pre-analysis preparation step (steps S601 to S603), a plating tank structure determination step (steps S611 to S616), and an in-plane uniformity optimization step (step S621 to step S623). ). This analysis process is performed using the usual analysis software.

In the pre-analysis preparation step, first, the hardware ‧ CAD (Computer-Aided Design) information is determined before determining the inter-electrode distance D1, the distance A1, the length B1, and the distance B'1 (step S601). Specifically, information such as the specifications of the square substrate S1, the substrate holder 11, the anode holder 60, the plating tank 39, and the electrical contacts 16 is set in the analysis software. Next, the process information is determined (step S602). Specifically, plating conditions such as a plating solution voltage value and a current value are set in the analysis software. Further, if necessary, the data of the preliminary experiment, the model data, and the boundary conditions are set in the analysis software (step S603).

Next, in the plating groove structure determining step, the opening shape of the anode mask is adjusted (step S611). Specifically, the numerical value of the opening shape of the tubular portion 51 of the adjustment plate 50, the inter-electrode distance D1, the distance A1 between the square substrate S1 and the tubular portion 51 of the adjustment plate 50, and the length B1 of the tubular portion 51 are defined. , set the respective specified values. Under this condition, for example, in a numerical range in which the optimum value of the opening shape of the tubular portion 51 is expected, the film thickness distribution of the square substrate S1 is calculated while changing the numerical value little by little. Among them, the numerical value of the opening shape of the anode mask 64 which minimizes the fluctuation of the film thickness distribution of the square substrate S1 is determined. Further, the above-mentioned predetermined values herein may be appropriately determined according to the rule of thumb. Further, the opening shape of the anode mask 64 of the present embodiment indicates the longitudinal and lateral lengths of the quadrangular opening corresponding to the shape of the square substrate S1. As the fluctuation of the film thickness distribution of the present embodiment, for example, a 3 σ value can be employed.

The opening shape of the tubular portion 51 of the adjustment plate 50 is adjusted (step S612). Specifically, each of the numerical values including the inter-electrode distance D1, the distance A1 between the square substrate S1 and the tubular portion 51 of the adjustment plate 50, and the length B1 of the tubular portion 51 is set as an anode mask 64. The opening shape is set to the value determined in step S611. Under this condition, for example, in a numerical range in which the optimum value of the opening shape of the tubular portion 51 is expected, the film thickness distribution of the square substrate S1 is calculated while changing the numerical value little by little. Among them, the numerical value of the opening shape of the tubular portion 51 having the smallest fluctuation in the film thickness distribution of the square substrate S1 is determined. In addition, the values specified herein may be appropriately determined in accordance with the rule of thumb. Moreover, the opening shape of the cylindrical portion 51 of the present embodiment indicates the longitudinal and lateral lengths of the quadrangular opening corresponding to the shape of the square substrate S1.

The discussion of the inter-electrode distance D1 is performed (step S613). Specifically, each of the numerical values including the distance A1 between the square substrate S1 and the tubular portion 51 of the adjustment plate 50 and the length B1 of the tubular portion 51 is set to a predetermined value as the opening shape of the anode mask 64. The numerical value determined in step S611 is set as the numerical value determined in step S612 as the opening shape of the tubular portion 51. Under these conditions, the value of the inter-electrode distance D1 is calculated, for example, within a numerical range in which the optimum value is expected, and the film thickness distribution of the square substrate S1 is calculated while changing the value every 5 mm. Among them, the value of the inter-electrode distance D1 at which the fluctuation of the film thickness distribution of the square substrate S1 is the smallest is determined. In addition, the values specified herein may be appropriately determined in accordance with the rule of thumb.

The discussion of the distance A1 between the tubular portion 51 and the square substrate S1 is performed (step S614). Specifically, a predetermined value is set as the length B1 of the tubular portion 51, and the numerical value determined in step S611 is set as the opening shape of the anode mask 64, and the opening shape of the tubular portion 51 is determined in step S612. The numerical value is set as the value of the value determined in step S613 as the inter-electrode distance D1. Under this condition, the value of the distance A1 is calculated, for example, within a numerical range in which the optimum value is expected to be included, and the film thickness distribution of the square substrate S1 is calculated while changing the numerical value little by little. Among them, the value of the distance A1 between the cylindrical portion 51 having the smallest fluctuation in the film thickness distribution of the square substrate S1 and the square substrate S1 is determined. In addition, the values specified herein may be appropriately determined in accordance with the rule of thumb.

The discussion of the length B1 of the tubular portion 51 is performed (step S615). Specifically, the numerical value determined in step S611 is set as the opening shape of the anode mask 64, and the numerical value determined in step S612 is set as the opening shape of the tubular portion 51, and is set as step S613 as the inter-electrode distance D1. The numerical value determined in the middle is set to the numerical value determined in step S614 as the distance A1 between the tubular portion 51 and the square substrate S1. Under this condition, the value of the length B1 is calculated, for example, within a numerical range in which the optimum value is expected to be included, and the film thickness distribution of the square substrate S1 is calculated while changing the value little by little. Among them, the value of the length B1 of the tubular portion 51 having the smallest fluctuation in the film thickness distribution of the square substrate S1 is determined. In addition, the values specified herein may be appropriately determined in accordance with the rule of thumb.

The distance B' 1 is automatically determined by determining the inter-electrode distance D1, the distance A1, and the length B1. Therefore, the analysis of the distance B' 1 may not be performed. Therefore, the respective values are determined based on the steps from step S611 to step S615. However, in the case where the above-mentioned predetermined value set in the discussion of each numerical value is inappropriate, it may be that each numerical value is not an appropriate numerical value. Therefore, in the present embodiment, it is also possible to repeat step S612 to step S615 a plurality of times (step S616).

In the second and subsequent steps S611, the opening shape of the tubular portion 51 of the adjustment plate 50, the inter-electrode distance D1, the distance A1 between the square substrate S1 and the cylindrical portion 51 of the adjustment plate 50, and the length of the tubular portion 51 are set. B1 is set to the value determined in step S613 to step S615, respectively, which has been executed. Under this condition, the value of the opening shape of the anode mask 64 having the smallest fluctuation in the film thickness distribution of the square substrate S1 is determined again (step S611). In other words, in the second and subsequent steps S612, the anode mask 64 having the smallest fluctuation in the film thickness distribution of the square substrate S1 is determined by using the numerical value determined based on the executed analysis without using the predetermined value determined by the empirical rule. The value of the opening shape.

Similarly, in the second and subsequent steps S612, the opening shape of the anode mask 64, the inter-electrode distance D1, the distance A1 between the square substrate S1 and the cylindrical portion 51 of the adjustment plate 50, and the length B1 of the tubular portion 51 are respectively It is set to use the executed step S611 and the values determined from step S613 to step S615. Under this condition, the value of the opening shape of the tubular portion 51 having the smallest fluctuation in the film thickness distribution of the square substrate S1 is determined again. (Step S612).

In the second and subsequent steps S613, the opening shape of the anode mask 64, the opening shape of the tubular portion 51 of the adjustment plate 50, the distance A1 between the square substrate S1 and the tubular portion 51 of the adjustment plate 50, and the cylindrical portion are obtained. The length B1 of 51 is set to a value determined in steps S611, S612, S614, and S615 that have been executed, respectively. Under this condition, the value of the inter-electrode distance D1 at which the fluctuation of the film thickness distribution of the square substrate S1 is the smallest is determined again.

In the second and subsequent steps S614, the opening shape of the anode mask 64, the opening shape of the tubular portion 51 of the adjustment plate 50, the inter-electrode distance D1, and the length B1 of the tubular portion 51 are respectively set to be executed. The values determined in step S611, step S612, step S613, and step S615. Under this condition, the value of the distance A1 between the square substrate S1 having the smallest fluctuation in the film thickness distribution of the square substrate S1 and the cylindrical portion 51 of the adjustment plate 50 is determined again.

In the second and subsequent steps S615, the opening shape of the anode mask 64, the opening shape of the cylindrical portion 51 of the adjustment plate 50, the inter-electrode distance D1, and the distance between the square substrate S1 and the cylindrical portion 51 of the adjustment plate 50 are obtained. A1 is set to the value determined in step S611 to step S614, respectively, which has been executed. Under this condition, the value of the distance A1 between the square substrate S1 having the smallest fluctuation in the film thickness distribution of the square substrate S1 and the cylindrical portion 51 of the adjustment plate 50 is determined again.

By repeating steps S611 to S615 a plurality of times as described above, it is possible to determine the respective values by using the respective values determined by the analysis without using the predetermined values determined by the empirical rule. Therefore, it is possible to determine the respective numerical values that can further reduce the fluctuation of the film thickness distribution of the square substrate S1. In addition, as long as the predetermined value determined by the empirical rule is appropriate, it is possible to determine the respective values of the fluctuation of the film thickness distribution of the square substrate S1 without repeating from step S611 to step S615 a plurality of times.

Next, in the in-plane uniformity optimization step, the adjustment of the opening shape of the anode mask 64 (step S621) and the adjustment of the opening shape of the tubular portion 51 of the adjustment plate 50 are performed (step S622). In the plating groove structure determining step from step S611 to step S616, the opening shape of the anode mask 64 and the opening shape of the cylindrical portion 51 of the regulating plate 50 have been determined. However, the shape of the openings determined in the plating groove structure determining step is determined mainly as information necessary for determining the inter-electrode distance D1, the distance A1, and the length B1. Therefore, step S621 and step S622 are surely performed to perform final adjustment of these opening shapes. Finally, additional calculation is performed as needed (step S623).

The inter-electrode distance D1, the distance A1, the length B1, and the distance B'1 obtained according to the analysis process described above have a predetermined correlation with the distance L1 from the center of the square substrate S1 to the electrical contact 16. FIG. 7 is a graph showing the correlation between the inter-electrode distance D1 obtained by the analysis process shown in FIG. 6 and the distance L1 from the center of the square substrate S1 to the electrical contact 16. FIG. 8 is a graph showing the correlation between the distance A1 obtained by the analysis process shown in FIG. 6 and the distance L1 from the center of the square substrate S1 to the electrical contact 16. FIG. 9 is a graph showing the correlation between the length B1 obtained by the analysis process shown in FIG. 6 and the distance L1 from the center of the square substrate S1 to the electrical contact 16.

In FIG. 7, a straight line SL1 is shown which connects the following plotted points: these points indicate that the distance L1 from the center of the square substrate S1 to the electrical contact 16 is 150 mm, 220 mm, and 280 mm, and 3 σ is the minimum. The point of the inter-electrode distance D1 of the value, where 3 σ represents the fluctuation of the film thickness distribution of the square substrate S1. In addition, in FIG. 7, it is shown that the distance L1 from the center of the square substrate S1 to the electrical contact 16 is 150 mm in the direction of reducing the distance between the poles based on the plotted point (D1) on the straight line SL1. The line sigma at which the 3 σ at 220 mm and 280 mm is the minimum value + 1% of the inter-electrode distance D1 is connected to the line SL2. Similarly, in FIG. 7, the distance L1 from the center of the square substrate S1 to the electrical contact 16 is indicated in the direction in which the distance between the poles is enlarged, with reference to the plotted point (D1) on the straight line SL1. The line sigma at which the 3 σ at 150 mm, 220 mm, and 280 mm is the minimum value +1% of the inter-electrode distance D1 is connected to the line SL3.

As shown in FIG. 7, there is a proportional relationship between the inter-electrode distance D1 when 3 σ is the minimum value and the distance L1 from the center of the square substrate S1 to the electrical contact 16 . Specifically, the straight line SL1 has a relationship of D1=0.53L1-18.7 mm. Further, the straight line SL2 has a relationship of D1=0.59L1-43.5mm, and the straight line SL3 has a relationship of D1=0.58L-19.8mm. The distance L1 from the center of the square substrate S1 to the electrical contact 16 is determined by the structure of the substrate holder 11 and the size of the square substrate S1. Therefore, the distance L1 is usually a predetermined value. Therefore, when the relational expression shown in FIG. 7 is obtained, as long as the distance L1 from the center of the square substrate S1 to the electrical contact 16 is obtained, the optimum inter-electrode distance D1 can be easily obtained.

In addition, when 3 σ indicating the fluctuation of the film thickness distribution of the square substrate S1 is within a minimum value of +1%, generally, the product has sufficient in-plane uniformity. Therefore, when the distance L1 is obtained, as the inter-electrode distance D1, it is preferably included in the range of 0.59L to 1-43.5 mm. D1 A value in the range of 0.58 L - 19.8 mm. Therefore, only the distance L1 is obtained, and the range of the appropriate inter-electrode distance D1 can be easily obtained.

In Fig. 8, a straight line connecting the plotted points is shown: these points are the minimum when the distance L1 from the center of the square substrate S1 to the electrical contact 16 is 160 mm, 225 mm, and 280 mm, and 3 σ is the minimum. The point of the distance A1 of the value, where 3 σ represents the fluctuation of the film thickness distribution of the square substrate S1. As shown in FIG. 8, there is a certain relationship between the distance A1 when 3 σ is the minimum value and the distance L1 from the center of the square substrate S1 to the electrical contact 16 . Specifically, as shown in FIG. 8, the distance A1 is independent of the value of the distance L1 from the center of the square substrate S1 to the electrical contact 16, and when the distance A1 is 20.8 mm, 3 σ is the minimum value. Therefore, when the relational expression shown in FIG. 8 is obtained, as long as the distance L1 from the center of the square substrate S1 to the electrical contact 16 is obtained, the optimum distance A1 can be easily obtained.

In Fig. 9, a straight line connecting the plotted points is shown: these points are the minimum values of 3 σ when the distance L1 from the center of the square substrate S1 to the electrical contact 16 is 160 mm, 220 mm, and 280 mm. The point of the length B1, where 3 σ represents the fluctuation of the film thickness distribution of the square substrate S1. As shown in FIG. 9, there is a certain relationship between the length B1 when 3 σ is the minimum value and the distance L1 from the center of the square substrate S1 to the electrical contact 16 . Specifically, as shown in FIG. 9, when the length B1 and the distance L1 from the center of the square substrate S1 to the electrical contact 16 satisfy the relationship of B1 = 0.33 L - 43.3 mm, 3 σ is the minimum value. Therefore, when the relational expression shown in FIG. 9 is obtained, as long as the distance L1 from the center of the square substrate S1 to the electrical contact 16 is obtained, the optimum length B1 can be easily obtained.

In the present embodiment, according to the analysis process shown in FIG. 6, the inter-electrode distance D1, the distance A1, and the length B1 shown in FIGS. 7 to 9 are obtained, and the distance from the center of the square substrate S1 to the electrical contact 16 is obtained. A chart of the correlation between L1. Next, the inter-electrode distance D1, the distance A1, the length B1, the distance B'1 of the plating tank 39 shown in FIG. 4 and FIG. 5, and the distance L1 from the center of the square substrate S1 to the electrical contact 16 are set to By satisfying the relationship shown in FIGS. 7 to 9, the plating groove 39 capable of reducing the film thickness distribution of the square substrate S1 can be easily formed.

The embodiments of the present invention have been described above, but the embodiments of the present invention have been made to facilitate the understanding of the present invention and are not intended to limit the present invention. It is a matter of course that the present invention can be modified or improved without departing from the gist thereof, and the present invention also includes equivalents thereof. In addition, it is possible to arbitrarily combine or omit each of the structural elements described in the scope of the claims and the scope of the invention in the range of at least a part of the above-mentioned problems, or at least a part of the effects.

Hereinafter, several methods disclosed in the present specification are described.

According to a first aspect, there is provided a plating apparatus for plating the square substrate using a substrate holder holding a square substrate. The plating apparatus includes: a plating tank configured to house the substrate holder holding the square substrate; and an anode, wherein the anode is disposed opposite to the substrate holder in the plating The inside of the groove. The substrate holder has electrical contacts, and the electrical contacts are configured to supply power to opposite sides of the square substrate. In the case where the shortest distance between the center of the substrate of the square substrate and the electrical contact is L1, and the distance between the square substrate and the anode is D1, the square substrate and the anode satisfy 0.59×L1-43.5mm D1 A relationship of 0.58 × L 1-19.8 mm is disposed in the plating tank.

According to the first aspect, by setting L1 and D1 to satisfy the above relationship, the film thickness distribution of the plating film formed on the square substrate can be reduced. In other words, as long as either one of L1 and D1 is obtained, based on the above relationship, the other of L1 and D1 capable of reducing the film thickness distribution of the plating film formed on the square substrate can be easily set.

According to a second aspect, in the plating apparatus of the first aspect, there is provided an adjustment plate disposed between the substrate holder and the anode, the adjustment plate having a cylindrical portion, the cylindrical shape The opening forms an opening for passing the power line. When the length of the tubular portion is B1, the tubular portion has a length that satisfies the relationship of B1=0.33×L1-43.3 mm.

According to the second aspect, by setting L1 and B1 to satisfy the above relationship, the film thickness distribution of the plating film formed on the square substrate can be reduced. In other words, as long as one of L1 and B1 is obtained, based on the above relationship, the other of L1 and B1 capable of reducing the film thickness distribution of the plating film formed on the square substrate can be easily set.

According to a third aspect, in the plating apparatus of the first aspect or the second aspect, there is provided an adjustment plate disposed between the substrate holder and the anode, the adjustment plate having a cylindrical portion, The tubular portion forms an opening through which the power line passes, and when the distance between the surface of the square substrate housed in the plating apparatus and the cylindrical portion is A1, the relationship of A1 = 20.8 mm is satisfied.

According to the third aspect, by setting L1 and A1 to satisfy the above relationship, the film thickness distribution of the plating film formed on the square substrate can be reduced. In other words, as long as one of L1 and A1 is obtained, based on the above relationship, the other of L1 and A1 capable of reducing the film thickness distribution of the plating film formed on the square substrate can be easily set.

According to a fourth aspect, there is provided a method of determining a plating tank structure: a substrate holder holding a square substrate; an anode holder holding an anode and having an anode mask that blocks a part of the anode; An adjustment plate disposed between the substrate holder and the anode holder, wherein the method of determining the plating groove structure determines an opening shape of the anode mask and an opening shape of a cylindrical portion of the adjustment plate And a distance between the square substrate and the anode, a distance between the square substrate and the cylindrical portion of the adjustment plate, and a length of the tubular portion of the adjustment plate. In the first step, the opening of the anode mask that minimizes fluctuations in the film thickness distribution of the square substrate is determined in a state where the respective values other than the opening shape of the anode mask are set to predetermined values. In the second step, the respective values other than the opening shape of the anode mask and the opening shape of the tubular portion of the adjustment plate are set to predetermined values, and the opening of the anode mask is opened. In the state in which the shape is the value determined in the first step, the numerical value of the opening shape of the tubular portion of the adjustment plate that minimizes the fluctuation in the film thickness distribution of the square substrate is determined; Each value of the distance between the square substrate and the adjustment plate and the length of the tubular portion of the adjustment plate is a predetermined value, and the opening shape of the anode mask is a value determined in the first step. The square substrate and the chamber having the smallest fluctuation in the film thickness distribution of the square substrate in a state in which the opening shape of the tubular portion of the adjustment plate is a value determined in the second step The numerical value of the distance of the anode; in the fourth step, the numerical value of the length of the tubular portion of the adjustment plate is set to a predetermined value, and the opening shape of the anode mask is set to a value determined in the first step. The opening shape of the tubular portion of the adjustment plate is set to a value determined in the second step, and the distance between the square substrate and the anode is set to a value determined in the third step. a state in which a distance between the square substrate having a minimum fluctuation in a film thickness distribution of the square substrate and the adjustment plate is determined; and a fifth step of forming an opening shape of the anode mask in the first process The determined value is such that the opening shape of the tubular portion of the adjustment plate is a value determined in the second step, and the distance between the square substrate and the anode is determined in the third step. The value of the adjustment plate that minimizes the fluctuation of the film thickness distribution of the square substrate in a state where the distance between the square substrate and the adjustment plate is a value determined in the fourth step. The length of the tubular portion.

According to the fourth aspect, the opening shape of the anode mask capable of reducing the film thickness distribution of the plating film formed on the square substrate, the opening shape of the tubular portion of the adjustment plate, and the square substrate and the substrate can be determined. The distance of the anode, the distance between the square substrate and the cylindrical portion of the adjustment plate, and the length of the cylindrical portion of the adjustment plate.

According to a fifth aspect, the method of the fourth aspect, further includes: a sixth step of causing the opening shape of the tubular portion of the adjustment plate to be a value determined in the second step, and causing the The distance between the square substrate and the anode is a value determined in the third step, and the distance between the square substrate and the adjustment plate is set to a value determined in the fourth step, and the adjustment plate is In a state where the length of the tubular portion is a value determined in the fifth step, the opening shape of the anode mask having the smallest fluctuation in the film thickness distribution of the square substrate is determined again; The opening shape of the anode mask is set to a value determined in the sixth step, and the distance between the square substrate and the anode is set to a value determined in the third step, and the square substrate and the square substrate are The distance of the adjustment plate is a value determined in the fourth step, and the length of the tubular portion of the adjustment plate is set to a value determined in the fifth step, and the determination is again performed. Fluctuation of film thickness distribution of square substrate The opening shape of the tubular portion of the small adjustment plate; in the eighth step, the opening shape of the anode mask is set to a value determined in the sixth step, and the adjustment plate is The opening shape of the tubular portion is a value determined in the seventh step, and the distance between the square substrate and the adjustment plate is set to a value determined in the fourth step, and the adjustment plate is In a state where the length of the tubular portion is a value determined in the fifth step, the distance between the square substrate and the anode having the smallest fluctuation in the film thickness distribution of the square substrate is determined again; The opening shape of the anode mask is set to a value determined in the sixth step, and the opening shape of the tubular portion of the adjustment plate is set to a value determined in the seventh step, and the The distance between the square substrate and the anode is a value determined in the eighth step, and the length of the tubular portion of the adjustment plate is set to a value determined in the fifth step, and is determined again. Fluctuation in film thickness distribution of the square substrate a distance between the small square substrate and the adjustment plate; and a tenth step of causing the opening shape of the anode mask to be a value determined in the sixth step to cause the tube of the adjustment plate The opening shape of the shape is a value determined in the seventh step, and the distance between the square substrate and the anode is a value determined in the eighth step, and the square substrate and the adjustment plate are set. In the state where the distance is the value determined in the ninth step, the length of the tubular portion of the adjustment plate having the smallest fluctuation in the film thickness distribution of the square substrate is determined again.

According to the fifth aspect, the opening shape of the anode mask in which the film thickness distribution of the plating film formed on the square substrate can be further reduced, the opening shape of the tubular portion of the adjustment plate, and the square substrate can be determined. a distance from the anode, a distance between the square substrate and the cylindrical portion of the adjustment plate, and a length of the cylindrical portion of the adjustment plate.

According to a sixth aspect, the fourth aspect or the fifth aspect, further comprising: a step of adjusting an opening shape of the anode mask; and a step of adjusting an opening shape of the tubular portion of the adjustment plate.

Claims (7)

A plating apparatus for plating the square substrate using a substrate holder holding a square substrate, comprising: a plating groove configured to house the substrate holder holding the square substrate; and an anode Arranging in the interior of the plating tank opposite to the substrate holder, the substrate holder has electrical contacts, and the electrical contacts are configured to supply power to opposite sides of the square substrate, in the square The distance between the substrate center of the substrate and the electrical contact is L1, and in the case where the distance between the square substrate and the anode is D1, the square substrate and the anode satisfy 0.59×L1-43.5 Mm D1 A relationship of 0.58 × L 1-19.8 mm is disposed in the plating tank.  The plating apparatus according to claim 1, wherein the plating apparatus has an adjustment plate disposed between the substrate holder and the anode, and the adjustment plate has a cylindrical portion, the tube The opening forms an opening for passing the power line, and when the length of the tubular portion is B1, the tubular portion has a length satisfying a relationship of B1=0.33×L1-43.3 mm.    The plating apparatus according to claim 1, wherein the plating apparatus has an adjustment plate disposed between the substrate holder and the anode, and the adjustment plate has a cylindrical portion, the tube The opening forms an opening for allowing the power line to pass, and when the distance between the surface of the square substrate housed in the plating apparatus and the cylindrical portion is A1, the relationship of A1 = 20.8 mm is satisfied.    The plating apparatus according to claim 2, wherein when the distance between the surface of the square substrate accommodated in the plating apparatus and the cylindrical portion is A1, the relationship of A1 = 20.8 mm is satisfied.    A method for determining a plating tank structure, wherein the plating tank houses: a substrate holder that holds a square substrate; an anode holder that holds an anode and has an anode mask that blocks a part of the anode; and a substrate disposed on the substrate An adjustment plate between the cage and the anode holder, the method of determining the plating groove structure determines an opening shape of the anode mask, an opening shape of a cylindrical portion of the adjustment plate, and the square substrate The numerical value of the distance from the anode, the distance between the square substrate and the tubular portion of the adjustment plate, and the length of the tubular portion of the adjustment plate, the determination of the plating groove structure In the first step, the opening shape of the anode mask in which the fluctuation in the film thickness distribution of the square substrate is minimized is determined in a state where the respective values other than the opening shape of the anode mask are set to predetermined values. In the second step, the respective values other than the opening shape of the anode mask and the opening shape of the tubular portion of the adjustment plate are set to predetermined values, and the anode is provided. The state in which the opening shape of the cover is a value determined in the first step, and determines the numerical value of the opening shape of the tubular portion of the adjustment plate in which the fluctuation in the film thickness distribution of the square substrate is the smallest; The numerical value of the distance between the square substrate and the adjustment plate and the length of the tubular portion of the adjustment plate is set to a predetermined value, and the opening shape of the anode mask is set in the first process. The determined value is such that the opening shape of the tubular portion of the adjustment plate is a value determined in the second step, and the square substrate having the smallest fluctuation in the film thickness distribution of the square substrate is determined. a numerical value of the distance from the anode; in the fourth step, the numerical value of the length of the tubular portion of the adjustment plate is set to a predetermined value, and the opening shape of the anode mask is made in the first process The determined value is such that the opening shape of the tubular portion of the adjustment plate is a value determined in the second step, and the distance between the square substrate and the anode is determined in the third step. State of the value Determining a distance between the square substrate having the smallest fluctuation in the film thickness distribution of the square substrate and the adjustment plate; and a fifth step of determining an opening shape of the anode mask in the first step The value is such that the opening shape of the tubular portion of the adjustment plate is a value determined in the second step, and the distance between the square substrate and the anode is a value determined in the third step. The cylindrical shape of the adjustment plate that minimizes the fluctuation of the film thickness distribution of the square substrate in a state where the distance between the square substrate and the adjustment plate is a value determined in the fourth step The length of the department.    The method of determining a plating tank structure according to claim 5, further comprising: a sixth step of causing an opening shape of the tubular portion of the adjusting plate to be a value determined in the second step, The distance between the square substrate and the anode is set to a value determined in the third step, and the distance between the square substrate and the adjustment plate is set to a value determined in the fourth step, and the In a state where the length of the tubular portion of the adjustment plate is a value determined in the fifth step, the opening shape of the anode mask having the smallest fluctuation in the film thickness distribution of the square substrate is determined again; In the step, the opening shape of the anode mask is set to a value determined in the sixth step, and the distance between the square substrate and the anode is set to a value determined in the third step, and the The distance between the square substrate and the adjustment plate is a value determined in the fourth step, and the length of the tubular portion of the adjustment plate is set to a value determined in the fifth step, and again. Determining the film thickness of the square substrate The opening shape of the tubular portion of the adjustment plate having the smallest fluctuation; and the eighth step of setting the opening shape of the anode mask to a value determined in the sixth step to cause the adjustment plate The opening shape of the tubular portion is a value determined in the seventh step, and the distance between the square substrate and the adjustment plate is set to a value determined in the fourth step, and the adjustment plate is In a state where the length of the tubular portion is a value determined in the fifth step, the distance between the square substrate and the anode having the smallest fluctuation in the film thickness distribution of the square substrate is determined again; The opening shape of the anode mask is set to a value determined in the sixth step, and the opening shape of the tubular portion of the adjustment plate is set to a value determined in the seventh step. The distance between the square substrate and the anode is a value determined in the eighth step, and the length of the tubular portion of the adjustment plate is set to a value determined in the fifth step. Redetermining the film thickness distribution of the square substrate And a distance between the square substrate having the smallest fluctuation and the adjustment plate; and a tenth step of setting the opening shape of the anode mask to a value determined in the sixth step to cause the adjustment plate The opening shape of the cylindrical portion is a value determined in the seventh step, and the distance between the square substrate and the anode is set to a value determined in the eighth step, and the square substrate and the square substrate are When the distance of the adjustment plate is the value determined in the ninth step, the length of the tubular portion of the adjustment plate having the smallest fluctuation in the film thickness distribution of the square substrate is determined again.    The method for determining a plating tank structure according to claim 5 or 6, further comprising: a step of adjusting an opening shape of the anode mask; and a step of adjusting an opening shape of the cylindrical portion of the adjusting plate .